Columns are well known devices designed to strip desired volatile components from a mixture of liquids often containing solids. Such columns require intimate and continuous contact of vapors moving upwards with liquid moving counter-currently downwards. Different designs for columns have been proposed, including columns packed with Raschig rings, saddles, etc., bubble-cap columns, and other variations designed to cause a continuous mixing and interfacing of downwardly flowing liquid with upwardly flowing vapors so as to cause the maximum amount of volatile components to vaporize in concentrated form from the liquid fed to the column. Such columns are frequently tall (10-15 ft.), and if joined to other equipment (such as a rectifying column), may be part of a single column of 25-35 ft. tall. Because they are so tall and of lightweight construction, these columns are not easy to clean. Boiling-out with caustic solution or strong acid solution together with injection of steam is not feasible because the head pressure of such a tall column of liquid is much too great to be contained by the ordinary column construction. Cleaning, therefore, must frequently be accomplished by dismantling the column and scraping the dismantled internal components to remove the formed encrustations. The cleaning procedures are especially important considerations when the liquid being treated in the column forms a heavy encrustation such as a fermented mash, because the scale which forms readily attaches itself to the surfaces in the column and clogs up the passageways. Need for cleaning is necessarily frequent with such feed stock and down-time may become a significant factor of cost when recovering alcohol from fermented mash.
It is an object of this invention to provide a novel and simple distillation column section which can be readily cleaned. Another object is to provide a distillation column section which is particularly useful in handling a liquid containing scale-forming components. Another object is to provide a novel parallelogram design of four distillation column sections. Still other objects will be apparent from the more detail description which follows.